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Mercury levels in hepatopancreas, muscle and exoskeleton tissues of male and female green tiger prawn, P.semisulcatus, from the Persian Gulf were compared. Significantly higher levels (p<0.05) of mercury in female prawn and hepatopancreas tissue were encountered (p<0.05). Significantly higher concentration (p<0.05) of the mercury was also observed in summer than in winter season. This variation could result in internal biological cycle of the organism or variation in bioavailability of mercury in environment.

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This study is aimed to investigate the effect of microbial Lipase enzymes in different concentration of 10,30 and 50 ppm and ckecking it effect on bugget`s quality. Physicochemical characteristics of bread such as moisture, volume, texture tough, color and intuitive traits are evaluated. The results revealed that there aren`t  any remarkable differences in smell, volume, taste, crust color, shape coordination, crack and rupture and exterior characteristics between experiments and control experiment in intuitive evaluation (P>0.5). Bread produced in 10,30 ppm values of  Lipase enzyme have more prominence  in  characteristics like inner texture , crust quality, improving the ability to br chewed, proper perforation of the texture than control experiment, but using 10 ppm Lipase showed the most prominence in receiving overall intuitive characteristics. According to the results of texture examinations, using10,30ppm concentrations lipase  is better than 50 ppm lipase. Bread produced with 10ppm lipase showed the maximum volume and best crumb color, and 30 ppm lipase enzyme the best crust color of the all, and it has the maximum moisture between experiments and it was a remarkable difference among all experiments (P<0.5).  

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Bakery products, like many processed foods, are subjected to the physical, chemical and microbiological spoilage. Mold growth is a problem that limits the shelf life of high and intermediate- moisture bakery products .Water activity is a physical property that has a direct implication for microbiological safety of food. Foods with lower water activities are quite shelf life since they contain small a mount of water available for microorganisms to use for growth. In this research, effects of polyols (Glycerin, Sorbitol, Propylene glycol), invert and glucose syrup on the quality of batter and cake were evaluated. Polyols, invert and glucose syrup at five levels (1, 2, 3, 4 and 5%) were considered as variable treatments. The results showed that, cakes containing with propylene glycol had higher specific volume of batter, less height of cake and higher moisture of cake (P<0.05). Propylene glycol and glycerol were significant different in decreasing water activity other than sorbitol, invert and glucose syrup (P<0.05). Cakes containing propylene glycol and glycerol were more than sorbitol shelf life, invert and glucose syrup. Samples of cakes containing invert had the lowest pH (P<0.05). Thus, the polyols can be used to increase the quality and shelf life of cake.

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The main purpose of this study was to use wheat germ in production of milk dessert. Therefore, wheat germ was first heated at 150 °C for 15 min, then milled to obtain particle sizes of 125, 210 and 354 micrometers. Samples were made with 10% sugar, 2% gelatin and 88% low-fat milk (1.5% fat) and different levels of wheat germ (2.5, 5, 7.5 and 10%, w/w). Different characteristics of the fresh product and after storage for 15 days at 4 °C were determined. The results showed that with increasing the amount of wheat germ, dry materials of the samples increased while the pH decreased. Changes in the particle size of the samples had no effect on the dry materials. Textural evaluations showed that with increasing the germ level, particle size and storage time, hardness, cohesiveness, chewiness and gumminess, increased while elasticity decreased. Studying the internal structure of the desserts using scanning electron microscopy showed that the uniformity of the samples increased with increasing the germ content in dessert formulation. Moreover, with increasing the percentage and particle size of the germ, the darkness, redness and yellowness of the desserts increased. The results showed that the syneresis of desserts reduced with increasing the level of the germ, however, changes in particle size of the germ had no effect on this parameter. Sensory evaluation results concluded that the samples were prepared with maximum amount of 7.5% germ with particle size of 125 micrometer were the most acceptable samples.

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The purpose of this research was to investigate the hydraulic parameters affecting the performance of the distillation column and the hydrodynamic characteristics of the flow field on the industrial scale-sieve tray using numerical simulation. Computational fluid dynamics method was used for analyzing and predicting flow behavior. The desired geometry including the space between two trays of the distillation column and the down comer region was considered. After plotting geometry, three dimensional grids were generated in Gambit software and the analysis of the flow field was traced in Fluent software. The Eulerian-Eulerian approach was applied to simulate two-phase flow and k-ε RNG model for turbulence modeling. Validation of the results was done successfully using Solari and Bell experiment data and the correlation presented by Colwell. The velocity distribution and volume fraction of liquid and gas in different zones were determined. The influence of inlet volumetric flow rate of liquid and gas, as well as the geometry of the weir, on parameters related to the tray performance such as clear liquid height and froth height were investigated. The results indicated that a better separation would occur in lower gas and liquid loads.